RotaryZZ

According to the manual, you may need this special tool for changing pads at the back. (Don't really know what it called!) It allows you to "turn" the caliper piston all the way back in so there will be enough room to fit the new pad.
My question is do you need to go back to Mazda to get that tool or is it something similar that you can buy at Sears or other hardware store??

red_rx8_red_int

I think you can do it without the tool. It will just take longer. I had my back brakes apart last week painting my calipers and was looking at the workshop manual. I would think that just by applying pressure for a while the caliper would go back in. Just my general experience with other car's brakes and from what I saw.

Southsider

I know that some mechanics simply use a C-clamp to push the pistons back down. They just twist it closed until the piston is all the back down.

devoid

I just use a fast adjusting C-clamp from autozone! It has an orange button on it, so you quickly adjust it down, squeeze it like a normal c-clamp, then quickly pull it back off...works great!

RotaryZZ

Isn't the C-clamp just pushing the piston straight back in? This may work for the front, but for the back, you're supposed to 'turn and push' the piston in at the same time. I may afraid it may damage the piston if you just apply the force straight down!

FastRX8

My 2 cents.

My previous MX-3 had these same type of calipers.
I was never able to use the C-clamp method on them.
It seems that the piston is actually some how threaded in.
Or, I should say, that it works like a regular screw would work.
Clockwise will thread it in, and give you more room to work with, and put the new pads on.
For my MX-3, I was able to get a large wrench, and place the open end of the wrench in the notches on the piston and twist.
I painted my calipers on the 8 last week.
I didn’t have a wrench large enough to do it the same way as the MX-3, so I used needle nose pliers.
Take a look at this picture.

http://www.drivewerks.com/catalog/sh...CAT500_pg5.htm

It is the best tool I’ve seen for this job. This tool catches all 4 notches, but the pliers, catching 2 notches opposite each other, worked just fine.


Good luck-
Cesar

FastRX8

Here's another link to the same tool with a drawing of how it works.
http://www.jcwhitney.com/autoparts/P...atalogId-10101

FastRX8

One last thing -
Remove the bottom bolt on the caliper, but leave the top bolt on. Loosen the top bolt enough so that you can swing the caliper up. You'll need the top bolt on in order to be able to apply the pressure to turn the piston.
At first it's a little tricky. If you use the needle nose pliers, you need to keep them open about 2 inches while trying to turn them at the same time. You might want to squeeze a small socket with the pliers to keep them open while turn them.

Hope this isn't too confusing. It's hard to paint a picture of this. (I should have paid more attention in Ms. Silbers creative writing class.)

Again, it's really not that difficult of a task. If I made it sound too difficult, PM me, and I can either call you or give you my number and you can call me.

- Cesar

smd3

you can get the tool at a parts store or autozone loan a tool program I think. You need a special tool to work on the rear callipers. Just buy a tool, I don't think they're that expensive.

rx8cited

I used a C-clamp for the front pistons and a pair of needle nose pliers (spread tips and use as a wide screwdriver) for the rear pistons with no issues. Just be gentle.

rx8cited

RotaryZZ

Excuse me for being ignorant, but what is a needle nose plier??

>http://www.drivewerks.com/catalog/shopcart/TOOL/POR_TOOL_CAT500_>pg5.htm
I've seen similar things selling at PepBoys. They may or may not have the right pattern for the 8 though. Does anyone actually try this tool and work on the 8??

Rotary Nut

Yes the the pistons on the rear pads have threads on them. This is so the emergency brakes work. when you pull up on the handle the cable pulls on a lever the TURNS the pistons in forcing the piston against the pads and rotors. There should be a set of dimples on the surface of the piston that allow small nibs on the special tool to engage as it is turned/tightened forcing the pistons back in.

Dark8

The one on the left.

VividRacing.com

Nice find on the tool. I used the needle nose pliers before with no problem but for $10 the part is totaly worth saving the tips of my needle nose.

RotaryZZ

Thanks for showing me the picture of the nose piler :-) I'm just thinking wouldn't the clamp (the tool on the right side of the picture) be a better fit for the job?
Btw, I'm wondering how much will the Mazda charge for their special tool?! The one sells by PepBoys or AutoZone may or may not fit the exact pattern of the piston on our car.

Ned M

iTrader: (2)

The brake SST and other options were covered in another recent thread accessed by searching on brake and SST:

https://www.rx8club.com/showthread.p...ight=brake+sst

rx8cited

Okay, this is getting really crazy . Standard pliers are not C-clamps! And what do people call needle nose pliers in other parts?

Here are the correct tools/pictures from Sears:

Lisle Disc Brake Piston Tool (for the rear pistons)

Craftsman Disc Brake Pad Spreader (for the front pistons)

I've never used these. My c-clamp and needle nose pliers worked fine.

rx8cited

scoop

I have not had a reason to pull the rear calipers on the 8 but I have done it many times on Audis and they sound about the same. Here are some rules of thumb and precautions:

1- The pistons turn in clockwise and I have seen three different styles of indentations on otherwise identical calipers, DON'T use a "C" clamp! (i.e. there is not just one brake tool, you will need one that matches the 8 as it sits now, a rebuilt one down the road could show up different) It takes many many turns to get them all the way in.
2- Over time the piston boot can stick to the piston, make sure it doesn't start to twist or it will tear. If it sticks to the piston, free it up first by gently prying it away.
3- After installing the pads DON'T start the car, pump the brakes a good 20-30 times with no brake boost to seat the pads in. If you do this with boost you may jam and destroy the calipers.
4- Make sure the boots on the parking brake cable and slider pins are all properly seated and not damaged.
5- Check your brake fluid level afterward, you may cause it to overflow when driving the pistons in.
6- Use the parking brake all the time, some rear calipers use that as their only adjustment method, I don't know on the 8.
7- You probably want to lube the guide pins or at least make sure they are moving freely.
8- You may also want to put a dab of high temp silicone at the caliper contact points on the pad backings to cut noise.
9- You may want to put a dabs of high temp silicone in the slot or holes on the piston where the tool attaches, otherwise that area can rust so badly that the tool will no longer be able to grip it down the road.

Rear calipers tend to be much more expensive than the fronts and have been very high maintenance items on cars I have driven so be very careful . . .

StealthTL

iTrader: (1)

Number one tip would be - buy the little tool gizmo, save your fine needle-nose pliers for their intended function. (The mark of a crappy mechanic is using screwdrivers as chisels etc.)

Number two seems to have been overlooked so far - take out the little phillips-head screws that hole the disc to the hub, and put some anti-seize slime on them.
In a couple of years, when you come to do some rotor or brake work, you will be cursing them up & down. They are not safety related, they just hold the disc on, while the wheel is off.
"Hear me now, and believe me later....." Hans & Frans

S

Ophitoxaemia

i dont know about the rx8, but one car i worked on had the screw-in type rear brakes and i used the tightener tool from my 4.25" angle grinder- perfect!

the manuals always specify some tool TYKSH67HSD67GHDS-433-11 which usually turns out to be a substitute for a vice grip. :D here's a translation manual: http://www.rucompatible.com/triumph/manuals.htm


james

rx8cited

OMG, another "crappy mechanic" just like myself with my needle nose pliers and "c-clamp" :D.

rx8cited

red_rx8_red_int

While were talking about brakes. Don't just fill the master cylinder when low. Check your brakes. Otherwise what happens is your brakes wear down, you don't notice the brake wear but your fluid appears low, you add more fluid, then shortly thereafter you find out you need new brakes. After you put on the new pads the fluid level shows too high, and you have to remove fluid. From my experience, unless you have a leak, your fluid will only be low when the pads are about gone.

I probably was wrong in my first post in this thread, I have never owned a car before with rear disc brakes, and because of the e-brake rear discs are clearly different than front discs. That said, I'm not sure that you really need a special tool (so I may have been right). Compress a little, use needle nose to rotate a little, compress a little more, needle nose again, repeat 3-4 times and you're done.

Ophitoxaemia

hehe, all you really need is vicegrips, a welder and a grinder to make anything fit... oh, and a big effing hammer.

james

Matt-man

This tool works too:

RotaryZZ

Matt-man,

Have you used that before on the 8?? I think I've seen that somewhere before and it was supposed to be used on GM or Ford cars!!